The invention relates to an illumination system for mounting on relatively long or hinged vehicles such as semi-trailers with tractors, articulating vehicles, 5th wheel trailers, buses, recreational vehicles and boat trailers for example. Hereinafter, for convenience, the invention will be described with relation to a semi-tractor and semi-trailer.
Semi-tractor and trailer rigs are difficult to maneuver in close quarters such as city streets and loading docks. Due to the extended fixed length of the semi-trailer, when pivotally connected to a tractor, wide radius turns are necessary. The driver of a semi-tractor must generally rely exclusively on outside rear view mirrors to view the area immediately beside the trailer while making a turn. When such semi-tractors and trailers are traveling straight on a road or highway, outside rear view mirrors are generally satisfactory, even at night, in providing such a view.
However, when the driver is turning or otherwise maneuvering the semi-trailer in close quarters, such as in city streets or near loading docks, and particularly at night, it is impossible for the driver to view the area around the rear trailer wheel. Since the length of the turning radius of the semi-tractor and trailer rig is dependent upon the position of the rear trailer wheel, this inability to adequately see the area around the rear trailer wheel often results in collisions between the side of the trailer and nearby objects or vehicles. In addition to the problems with close quarter maneuvering, to safely complete the act of changing lanes on a multi-lane highway, a driver needs to be able to see any objects which are adjacent the side of the trailer.
One method of dealing with the problem during close quarter maneuvering is for the driver to make a series of small incremental moves, each one of a few feet. With each move, the driver must get out of the tractor to check the progress. These steps are repeated many times until the trailer is satisfactorily turned past any close quarter objects. While this method is often instructed by trucking companies, and is considered mandatory by the Department of Transportation, it is seldom used by drivers for reasons of inconvenience and time consumption. Of course, the method is not available to a driver while changing lanes on a highway. Instead, the "best guess" method is often used where the driver simply uses the extremely limited visual information available from the driver's seat and guesses the location of the trailer relative to his surroundings. Needless to say, this method results in many unnecessary incidents and accidents.
It is clear then, that a safe and reliable illumination system for lighting the area immediately adjacent the rear wheel of a semi-trailer is needed for enhanced safety. Such an illumination system should light the pavement and any objects around the rear trailer wheel during turns or lane changes so that the driver is made aware of the proximity of the trailer relative to surrounding objects. At the same time, to avoid distracting the truck driver and the drivers of surrounding vehicles, such an illumination system should preferably be turned on only when needed.